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The Energy Portal
Welcome to Wikipedia's Energy portal, your gateway to energy. This portal is aimed at giving you access to all energy related topics in all of its forms.
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A plasma lamp, using electrical energy to create plasma light, heat, movement and a faint sound

In physics, energy is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement in the International System of Units (SI) of energy is the joule, which is the energy transferred to an object by the work of moving it a distance of one metre against a force of one newton.

Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object's position in a force field (gravitational, electric or magnetic), the elastic energy stored by stretching solid objects, the chemical energy released when a fuel burns, the radiant energy carried by light, and the thermal energy due to an object's temperature.

Mass and energy are closely related. Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy. For example, after heating an object, its increase in energy could in principle be measured as a small increase in mass, with a sensitive enough scale.

Living organisms require energy to stay alive, such as the energy humans get from food. Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The processes of Earth's climate and ecosystem are driven by the radiant energy Earth receives from the Sun and the geothermal energy contained within the earth. (Full article...)

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Escape E85 Flex Fuel Hybrid WAS 2010 8941.JPG
A flexible-fuel vehicle (FFV) (or flex-fuel vehicle) is an alternative fuel vehicle with an internal combustion engine designed to run on more than one fuel, usually gasoline blended with either ethanol or methanol fuel, and both fuels are stored in the same common tank. The most common commercially available FFV in the world market is the ethanol flexible-fuel vehicle, with around 21 million automobiles, motorcycles and light duty trucks sold worldwide by mid 2010, and concentrated in four markets, Brazil (10.6 million), the United States (9.3 million), Canada (more than 600,000), and Europe, led by Sweden (199,000). Also a total of 183,375 flexible-fuel motorcycles were sold in Brazil in 2009. In addition to flex-fuel vehicles running with ethanol, in Europe and the US, mainly in California, there have been successful test programs with methanol flex-fuel vehicles, known as M85 flex-fuel vehicles.

Though technology exists to allow ethanol FFVs to run on any mixture of gasoline and ethanol, from pure gasoline up to 100% ethanol (E100), North American and European flex-fuel vehicles are optimized to run on a maximum blend of 15% gasoline with 85% anhydrous ethanol (called E85 fuel). This limit in the ethanol content is set to reduce ethanol emissions at low temperatures and to avoid cold starting problems during cold weather, at temperatures lower than 11 °C (52 °F). The alcohol content is reduced during the winter in regions where temperatures fall below 0 °C (32 °F) to a winter blend of E70 in the U.S. or to E75 in Sweden from November until March. Brazilian flex fuel vehicles are optimized to run on any mix of E20-E25 gasoline and up to 100% hydrous ethanol fuel (E100).

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Stromboli Eruption Crop1.png

Photo credit: From an image by Wolfgang Beyer
Strombolian volcanic eruptions can eject incandescent cinder, lapilli and lava bombs to altitudes of tens to hundreds of meters.

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Selected biography

Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for the development of quantum theory. Fermi won the 1938 Nobel Prize in Physics for his work on induced radioactivity.

Fermi was well-known for his simplicity in solving problems. Whenever possible, he avoided complicated mathematics and obtained quick results based on order of magnitude estimates. Fermi also meticulously recorded his calculations in notebooks, and later used to solve many new problems that he encountered based on these earlier known problems.

After accepting the 1938 Nobel Prize in Stockholm, Fermi immigrated to New York with his family to escape the anti-Semitic laws of Fascist Italy, as his wife Laura was Jewish.

After working at Columbia University, Fermi went to the University of Chicago and began studies that led to the construction of the world's first nuclear reactor Chicago Pile-1 (CP-1). The first artificial, self-sustaining, nuclear chain reaction was initiated within CP-1, on December 2, 1942.

In the news

5 July 2022 –
South Korea's inflation reaches a 24-year record, as the country struggles with increasing energy and food prices. (Nikkei)
28 June 2022 – 2019–present Sri Lankan economic crisis, 2021–2022 global energy crisis
Sri Lanka's power and energy minister Kanchana Wijesekera announces that the government will lift restrictions on fuel imports in response to the country's energy crisis, ending a fuel duopoly between the state-owned Ceylon Petroleum Corporation and the Indian government-owned Lanka IOC. (International Business Times)
Sri Lanka suspends sales of fuel for non-essential vehicles. For the next two weeks, only buses, trains and vehicles used for medical services and transporting food will be allowed to refuel. (BBC News)
27 June 2022 –
The Japanese government asks the public to conserve energy and to prepare for power outages as the country faces a heat wave. (AP)
21 June 2022 – 2021–2022 global energy crisis
Lebanon, Egypt and Syria sign an agreement to supply Egyptian gas to a power plant in northern Lebanon through Syria. However, the World Bank, which is financing the deal, must validate the agreement before it can take effect. (The Independent)

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